The project originally concerned bovine mannosidosis as a model of human lysosomal storage diseases but has been extended to include bovine Glycogen storage (type II), canine Gaucher disease and ovine ceroid-lipofuscinosis. Emphasis is on pathogenesis of these diseases, heterozygote detection and therapy. Collaborative research is an important aspect of the project. Currently, emphasis is on fully defining the ovine ceroid-lipofuscinosis model and seeking to deduce the pathogenesis of lesions and the nature of the underlying biochemical defect. Studies include (1) a time - course study of retinal changes using histological, ultrastructural and electroretinographic techniques; (2) unsaturated fatty acid profiles of phospholipids from affected and control sheep; (3) an analysis of lipids and other substances in the storage bodies. Collaborative studies on mannosidosis concern the origin of storage oligosaccharides in urine and the structure of such oligosaccharides as well as a study of changes in neuronal processes using Golgi impregnations. The canine Gaucher disease project mainly concerns detection of new cases and efforts to develop a colony.